Sinusitis is a condition affecting over 35 million Americans, and similarly large populations in the rest of the developed world. Sinusitis occurs when one or more of the four paired sinus cavities (i.e., maxillary, ethmoid, frontal, sphenoid) becomes obstructed. Normally the sinus cavities, each of which are lined by mucosa, produce mucous which is then moved by beating cilia from the sinus cavity out to the nasal cavity and down the throat. The combined sinuses produce approximately one liter of mucous daily, so the effective transport of this mucous is important to sinus health.
Each sinus cavity has an opening into the nasal passage called an ostium. When the mucosa of one or more of the ostia or regions near the ostia become inflamed, the egress of mucous is interrupted, setting the stage for an infection and/or inflammation of the sinus cavity, i.e., sinusitis. Infection/inflammations of the maxillary and/or ethmoid sinuses make up the vast majority of cases of sinusitis, with far fewer cases involving the sphenoids and frontals. Though many instances of sinusitis may be treatable with antibiotics, but in some cases sinusitis persists for months or more, a condition called chronic sinusitis, and may not respond to medical therapy. Some patients are also prone to multiple episodes of sinusitis in a given period of time, a condition called recurrent sinusitis.
One method of treating sinusitis in a patient includes the process of forming an artificial access passageway into a sinus cavity of the patient in order to access and treat the sinus ostium (outflow tract). For example, an access passageway may be formed in canine fossa region of the patient. One or more working instruments may then be positioned within the access passageway and into the sinus cavity. These instruments may include, for example, an endoscope, cannula, guide wire, balloon dilation catheter, irrigation catheter, aspiration catheter, drug delivery catheter, or the like. U.S. patent application Ser. Nos. 11/379,691 and 11/623,740, which are incorporated by reference as if set forth fully herein, describe various working instruments configured for placement into a sinus cavity via the artificially-formed access passageway.
Generally, once access into the particular sinus cavity (e.g., maxillary sinus) has been gained, and a working device is intended to be placed into the sinus cavity, it is desirable to be able to re-orient the path that such a device takes within the sinus. For example, the access into the sinus may be made by an access tool oriented along a particular angle, but subsequently, a working device may require being oriented along a different path, e.g., a path directed toward the sinus ostium.
There is a clear need for devices and methods that permit external access to a sinus cavity that also enable re-orientation of the access passageway to accommodate the various working instruments that may be employed to treat sinusitis or other condition.